Abstract:
A heat exchanger includes a pair of substantially concentric tubes defining a first flow path between the tubes, and a second flow path being defined by one of an inner one of the pair of tubes and an outer one of the pair of tubes. A fin is supported between the concentric tubes along the first flow path and surrounding an outer perimeter of the inner one of the pair of tubes, a first side of the fin being secured to one of the pair of tubes. A sleeve extends around a second side of the fin. An elastic element is positioned between the sleeve and another of the pair of tubes for biasing the sleeve into engagement with the second side of the fin and substantially sealing a bypass around the fin between the other of the pair of tubes and the sleeve.